There are well known devices for measuring the stature of persons. Such devices generally include an emitter/receiver device which emits an electric signal in the form of an ultrasonic pulse, and, conversely, transforms a received ultrasonic pulse to an electric signal, a microprocessor, a device for displaying the stature of the examined person, and at least one device indicating the end of the stature measuring operation. The microprocessor communicates with the emitter/receiver device, with the display device and with at least an indicating device, through an input/output port and the corresponding buffers. The emitter/receiver device includes a transducer transforming an electric signal to an ultrasonic pulse in both emission and receive directions, an oscillator connected to the transducer in the emitting network, and a filter, an amplifier and an alternating/continuous converter series connected in the receive network.
Such apparatus for measuring the stature of persons suffer from the drawback that the amplifier gain is constant, so that its behavior at different distances is not optimum. If the gain is made high in order that the amplification is enough for great distances, it becomes too high for small distances and picks up noises providing wrong signals.
There are known as well electronic scales comprising a load cell, an analogic/digital converter device, a microprocessor and a display for the weight placed onto the load cell. The microprocessor communicates with the analogic/digital converter device and the display through an input/output port.
These scales show the drawback that it is necessary to adjust the zero or offset and the bottom of scale or gain, for each scales.
On the other hand, owing to the functional relation binding the person weight and stature, there is a experienced need for an integrated apparatus for measuring the stature of persons and electronic scales adapted to furnish, besides of their own data about the stature and the weight of a person in one and the same apparatus, as well a comparison of the indicated weight with the ideal weight corresponding to the indicated stature of the same person.